US4364838AExpiredUtility

Liquid crystal mixtures

80
Assignee: HOFFMANN LA ROCHEPriority: Nov 14, 1979Filed: Nov 10, 1980Granted: Dec 21, 1982
Est. expiryNov 14, 1999(expired)· nominal 20-yr term from priority
Inventors:Arthur BollerAlfred GermannMartin SchadtAlois Villiger
C07D 239/26C07D 319/06C09K 19/46
80
PatentIndex Score
12
Cited by
33
References
37
Claims

Abstract

Liquid crystalline mixtures comprising trans-phenyldioxane, phenylpyrimidine and phenylbenzoate compounds which are useful in electro-optical apparatuses are disclosed.

Claims

exact text as granted — not AI-modified
We claim: 
     
       1. A liquid crystalline mixture comprising: (a) about 10 to about 75 mol percent of at least one trans-phenyl-dioxane of the formula: ##STR19##  wherein R 1  is straight chain alkyl of 3 to 7 carbon atoms; (b) about 5 to about 30 mole percent of at least one phenylpyrimidine of the formula: ##STR20##  wherein R 1  is as above; and (c) about 2 to about 20 mol percent of at least one phenylbenzoate of the formula: ##STR21##  wherein R 2  is straight chain alkyl of 2 to 7 carbon atoms.   
     
     
       2. The liquid crystalline mixture of claim 1 wherein R 1  of compound I is propyl, butyl or pentyl. 
     
     
       3. The liquid crystalline mixture of claim 1 wherein R 1  of compound VII is pentyl or heptyl. 
     
     
       4. The liquid crystalline mixture of claim 1 wherein R 2  of compound VIII is ethyl, butyl or pentyl. 
     
     
       5. The liquid crystalline mixture of claim 1 wherein compound I is present in the mixture in an amount of about 30 to about 70 mol percent. 
     
     
       6. The liquid crystalline mixture of claim 1 wherein compound VII is present in the mixture in an amount of about 10 to about 25 mol percent. 
     
     
       7. The liquid crystalline mixture of claim 1 wherein compound VIII is present in the mixture in an amount of from about 5 to about 17 mol percent. 
     
     
       8. The liquid crystalline mixture of claim 1 further comprising up to about 15 mol percent of at least one compound of the formula: ##STR22## wherein at least one of rings A and B is trans-1,4-disubstituted cyclohexane and the other is trans-1,4-disubstituted cyclohexane or aromatic, and R is straight chain alkyl of 1 to 10 carbon atoms, straight chain alkoxy of 1 to 10 carbon atoms or C 2  H 5  --CH(CH 3 )--(CH 2 ) n  --, and n is an integer of 1 to 3. 
     
     
       9. The liquid crystalline mixture of claim 8 wherein compound V has the formula: ##STR23## R is straight chain alkyl of 1 to 10 carbon atoms, straight chain alkoxy of 1 to 10 carbon atoms or C 2  H 5  --CH(CH 3 )--(CH 2 ) n  --, and n is an integer of 1 to 3. 
     
     
       10. The liquid crystalline mixture of claim 9 wherein R is straight chain alkyl of 2 to 7 carbon atoms. 
     
     
       11. The liquid crystalline mixture of claim 8 wherein compound V has the formula: ##STR24## R is straight chain alkyl of 1 to 10 carbon atoms, straight chain alkoxy of 1 to 10 carbon atoms or C 2  H 5  --CH(CH 3 )--(CH 2 ) n  --, and n is an integer of 1 to 3. 
     
     
       12. The liquid crystalline mixture of claim 11 wherein R is straight chain alkyl of 2 to 7 carbon atoms. 
     
     
       13. The liquid crystalline mixture of claim 8 wherein ring B of compound V is aromatic. 
     
     
       14. The liquid crystalline mixture of claim 13 wherein compound V has the formula ##STR25## R is straight chain alkyl of 1 to 10 carbon atoms, straight chain alkoxy of 1 to 10 carbon atoms or C 2  H 5  --CH(CH 3 )--(CH 2 ) n  --, and n is an integer of 1 to 3. 
     
     
       15. The liquid crystalline mixture of claim 14 wherein R is straight chain alkyl of 2 to 7 carbon atoms. 
     
     
       16. The liquid crystalline mixture of claim 15 wherein R is ethyl, pentyl or heptyl. 
     
     
       17. The liquid crystalline mixture of claim 8 wherein compound V is present in the mixture in an amount of about 2 to about 10 mol percent. 
     
     
       18. The liquid crystalline mixture of claim 1 further comprising up to about 30 mol percent of at least one trans-cyclohexane carboxylic acid phenyl ester of the formula: ##STR26## wherein R 1  is straight chain alkyl of 3 to 7 carbon atoms and R 3  is cyano or straight chain alkoxy of 1 to 3 carbon atoms. 
     
     
       19. The liquid crystalline mixture of claim 18 wherein R 1  of compound IX is propyl, butyl or pentyl and R 3  is methoxy, ethoxy or propyloxy. 
     
     
       20. The liquid crystalline mixture of claim 19 wherein compound IX is trans-4-propylcyclohexane carboxylic acid p-cyano-phenyl ester, trans-4-butylcyclohexane carboxylic acid p-cyanophenyl ester, trans-4-pentylcyclohexane carboxylic acid p-cyanophenyl ester, trans-4-butylcyclohexane carboxylic acid p-(ethoxy)phenyl ester, trans-4-pentylcyclohexane carboxylic acid p-(methoxy)phenyl ester or trans-4-pentylcyclohexane carboxylic acid p-(propyloxy)phenyl ester. 
     
     
       21. The liquid crystalline mixture of claim 18 wherein compound IX is present in the mixture in an amount of about 10 to about 30 mol percent. 
     
     
       22. The liquid crystalline mixture of claim 1 further comprising up to about 30 mol percent of at least one Schiffs base of the formula: ##STR27## wherein R 1  is straight chain alkyl of 3 to 7 carbon atoms. 
     
     
       23. The liquid crystalline mixture of claim 22 wherein compound X is present in the mixture in an amount of about 10 to about 25 mol percent. 
     
     
       24. The liquid crystalline mixture of claim 22 wherein R 1  is propyl, butyl or hexyl. 
     
     
       25. The liquid crystalline mixture of claim 8 consisting of compounds I, V, VII and VIII. 
     
     
       26. The liquid crystalline mixture of claim 25 consisting of p-(trans-5-propyl-m-dioxan-2-yl)benzonitrile, p-(trans-5-butyl-m-dioxan-2-yl)benzonitrile, p(trans-5-pentyl-m-dioxan-2-yl)benzonitrile, p-(5-pentyl-2-pyrimidinyl)benzonitrile, p-(5-heptyl-2-pyrimidinyl)benzonitrile, p-ethylbenzoic acid p'-cyanophenyl ester, p-butylbenzoic acid p'-cyanophenyl ester and trans-p-[5-(4-pentylcyclohexyl)-2-pyrimidinyl]benzonitrile. 
     
     
       27. The mixture of claim 26 consisting of about 19 mol percent p-(trans-5-propyl-m-dioxan-2-yl)benzonitrile, about 26 mol percent p-(trans-5-butyl-m-dioxan-2-yl)benzonitrile, about 15 mol percent p-(trans-5-pentyl-m-dioxan-2-yl)benzonitrile, about 6.5 mol percent p-(5-pentyl-2-pyrimidinyl)benzonitrile, about 12 mol percent p-(5-heptyl-2-pyrimidinyl)benzonitrile, about 7.5 mol percent p-ethylbenzoic acid p'-cyanophenyl ester, about 6 mol percent p-butylbenzoic acid p'-cyanophenyl ester and about 8 mol percent trans-p-[5-(4-pentylcyclohexyl)-2-pyrimidinyl]benzonitrile. 
     
     
       28. A liquid crystalline mixture comprising: (a) about 10 to about 75 mol percent of a trans-phenyldioxane of the formula: ##STR28##  wherein R 1  is straight chain alkyl of 3 to 7 carbon atoms; (b) about 5 to about 30 mol percent of a phenylpyrimidine of the formula: ##STR29##  wherein R 1  is as above; (c) about 2 to about 20 mol percent of a phenylbenzoate of the formula: ##STR30##  wherein R 2  is straight chain alkyl of 2 to 7 carbon atoms; (d) about 0 to about 15 mol percent of a compound of the formula: ##STR31##  wherein at least one of rings A and B is trans-1,4-disubstituted cyclohexane and the other is trans-1,4-disubstituted cyclohexane or aromatic and R is straight chain alkyl of 1 to 10 carbon atoms, straight chain alkoxy of 1 to 10 carbon atoms or C 2  H 5  --CH(CH 3 )--(CH 2 ) n  --, and n is an integer of 1 to 3;   (e) about 0 to about 30 mol percent of a trans-cyclohexane carboxylic acid phenyl ester of the formula: ##STR32##  wherein R 1  is straight chain alkyl of 3 to 7 carbon atoms and R 3  is cyano or straight chain alkoxy of 1 to 3 carbon atoms; and   (f) about 0 to about 30 mol percent of a Schiffs base of the formula: ##STR33##  wherein R 1  is straight chain alkyl of 3 to 7 carbon atoms.   
     
     
       29. The liquid crystalline mixture of claim 28 wherein compound I is present in the mixture in about 30 to about 70 mol percent. 
     
     
       30. The liquid crystalline mixture of claim 28 wherein compound VII is present in the mixture in about 10 to about 25 mol percent. 
     
     
       31. The liquid crystalline mixture of claim 28 wherein compound VIII is present in the mixture in about 5 to about 17 mol percent. 
     
     
       32. The liquid crystalline mixture of claim 28 wherein compound V is present in the mixture in about 2 to about 10 mol percent. 
     
     
       33. The liquid crystalline mixture of claim 28 wherein compound IX is present in the mixture in about 10 to about 30 mol percent. 
     
     
       34. The liquid crystalline mixture of claim 28 wherein compound X is present in the mixture in about 10 to about 25 mol percent. 
     
     
       35. A liquid crystalline mixture comprising: (a) about 30 to about 70 mol percent of one or more trans-phenyl-dioxanes of the formula: ##STR34##  wherein R 1  is propyl, butyl or pentyl; (b) about 10 to about 25 mol percent of one or more phenylpyrimidines of the formula: ##STR35##  wherein R 1  is pentyl or heptyl; (c) about 5 to about 17 mol percent of one or more phenylbenzoates of the formula: ##STR36##  wherein R 2  is ethyl, butyl or pentyl; (d) about 2 to about 10 mol percent of one or more compounds of the formula: ##STR37##  wherein R is ethyl, pentyl or heptyl; (e) about 10 to about 30 mol percent of one or more trans-cyclohexane carboxylic acid phenyl esters of the formula: ##STR38##  wherein R 1  is propyl, butyl or pentyl and R 3  is cyano, methoxy, ethoxy or propyloxy; and   (f) about 10 to about 25 percent of one or more Schiffs bases of the formula: ##STR39##  wherein R 1  is propyl, butyl or hexyl.   
     
     
       36. In an electro-optical liquid crystal display containing a liquid crystalline mixture having positive dielectric anisotrophy, the improvement wherein the liquid crystalline mixture comprises: (a) about 10 to about 75 mol percent of a trans-phenyl-dioxane of the formula: ##STR40##  wherein R 1  is straight-chain alkyl of 3 to 7 carbon atoms; (b) about 5 to about 30 mol percent of a phenylpyrimidine of the formula: ##STR41##  wherein R 1  is as above; and (c) about 2 to about 20 mol percent of a phenylbenzoate of the formula: ##STR42##  wherein R 2  is straight-chain alkyl of 2 to 7 carbon atoms.   
     
     
       37. A twisted-nematic, rotational electro-optic display improved as per claim 36.

Cited by (0)

No later patents cite this yet.

References (0)

No backward citations on record.